In tube mills for grinding and drying materials a drying chamber which serves for preliminary drying of the material to be ground frequently is arranged in advance of the actual grinding chamber. This drying chamber and the transition wall between it and the grinding chamber are often exposed to severe wear. The replacement of worn parts, and particularly the transition wall, generally necessitates shutting down of the whole grinding operation for a long period of time since for this purpose all the grinding balls have to be removed from the grinding chamber and put back in again after the repair has been carried out.
An object of the invention is to provide a tube mill of the type referred to and which enables the time during which the grinding plant is shut down for maintenance and repair work in the region of the drying chamber and the transition wall to be reduced to a minimum.